Hyper-text-transfer-protocol (HTTP) adaptive streaming (HAS) is emerging as a popular approach to streaming video-on-demand and real-time content. With regard to video-on-demand, for example, HAS is adaptive in the sense that the video quality can be adjusted based on the bandwidth or data rate available between the HAS server and a respective HAS client. However, each HAS client individually adapts its video quality independent of other HAS clients sharing the same resources.
Mobile HAS is rapidly becoming the preferred technology for watching video-on-demand and real-time multimedia content on mobile devices. As the use of mobile HAS increases, handling congestion for mobile HAS related traffic has become increasingly important for wireless service providers. Similar to wireline HAS, mobile HAS is also adaptive in the sense that the video quality can be adjusted based on the bandwidth or data rate available between the HAS server and a respective mobile HAS client.
For the most part, mobile HAS currently utilizes wireless Best Effort (BE) data connections. However, this is problematic when a wireless access network becomes congested because the HAS adaptation cannot timely identify access network congestion conditions, and thus, the prohibitively high data load on the wireless network caused by mobile HAS traffic persists, which results in delays, packet loss, escalation of congestion conditions, etc. This is especially true for 3rd Generation Partnership Project Long-Term Evolution (3GPP LTE) networks that allow individual clients to receive about 2-4 Mb/sec data streams, in which case about 8-10 mobile HAS clients can easily overload a serving eNode B or cell. Greedy non-cooperating client behavior where each mobile HAS client attempts to obtain maximal available cell throughput further contributes to the congestion problem, while adding unfairness in video quality distribution.
From the end user perspective, the congestion problem manifests itself in oscillating video quality with video freezes. From the wireless service provider's perspective, over-the-top HAS traffic is considered one of the main contributors to the network congestion itself.